depressurize
verb [ I or T ] (UK usually depressurise) uk/ˌdiːˈpreʃ.ə.raɪz/ us/ˌdiːˈpreʃ.ə.raɪz/
（使）（密闭空间，尤指机舱）失压
to (cause a closed space, especially the inside of an aircraft to) become lower in air pressure
If the cabin depressurizes, oxygen masks will automatically drop down. 如果机舱失压，氧气面罩就会自动落下来。
Synonym: decompress
Opposite: pressurize